James marspiall



(N o Model I I J. MARSHALL. QUADRUPLE EXPANSION ENGINE.

1%. 503,056, Patented Au .8',*189.s.

i Nrinn STATES JAMES MARSHALL, OF ITEEDS, ENGLAND.

QUADRUPLE-EXPANSION ENGINE.

SPECIFICATION forming part of Letters Iiatent No. 503,056, dated August 8, 1893. Application filed August 31, 1892. Serial No. 444,679. (No model.) Patented in England September 2, 1891, N0. 14,857i

To all whom it may concern:

Be it known that I, J AMEs MARSHALL, a citizen of England, residing at the Steam Plow Works, Leeds, in the co'untyof York, England, have invented certain new and useful Improvements in Quadruple-Expansion Engines, (for which I have obtained Letters Patent in Great Britain, dated September 2, 1891, No. 14,857,) of which the following is a specification.

and out.of single or double acting quadruple expansion engines with tandem cylinders. I will proceed to describe the construction and operation of the said valves with reference to the accompanying drawing, in which the figure is a vertical section of single acting quadruple expansion engines, with tandem cylinders, with the said'valve apparatus applied thereto.

The letter A indicates the high pressure cylinder; A the second cylinder; A the third, and A the fourth cylinder. This last cylinder is made double acting, the steam being made to pass from the top to the under side of the piston, in order by its further expansion, to take the load off the crank on the upstroke.

E is the lining to the valve chamber having rings of holes or slots communicating with the several annular passages in the body of the chamber; p p F is the main cylindrical valve, and G is the expansionvalvei E is the high pressure steam supply to the extension E of the valve chamber E, from which it enters the extension F of the main valve F, and is admitted to the cylinder A by the ports Q of the valve F when these communicate wit-h the port L of the cylinder A by means of the annular passage K communicating with such port, the admission ofsteam being controlled by the expansion valve G;-

1 In the position of the pistons and valves shown on the drawing, the piston S of the high pressure cylinder has jnstpompleted its stroke, and the steam is' just about to pass into-the second cylinder AF for which purpose the port Q of the valve is in communication withthe passage K, and is aboutto establish a communication through annular passage R and ports Q 'with passage K and port L of cylinder At the same time, the steam which has previously passed from cylinder'A to cylinder A is about to pass thence into cylinder A through port N, annular passage K port Q annular passage R, port Q,

annular passage K and'port N into cylinderA on the upper side of piston T. At the same timealso steam which had previously been admitted from the upper side to the under side of piston Tpasses to the exhaust outlet U through port 0 and annular passages Q and K On the valve F being moved into the opposite position to that shown on the drawing, high pressure steam is admitted to cylinder Athrough ports Q and passage K as before "described, while at the same time the steam passes from cylinder A through port L, annular passage K ports Q passage R, port Q passage'K and port N into cylinder A and at the same time also steam passes from the upper side of piston T through port N, passage K, port Q passage R, port Q passage K and port 0 to the under side of piston T.

It will be evident that engines constructed as above described may be arranged either vertically, horizontally or inclined.

The present invention differs from the triple expansion engine described and claimed in my application, Serial No. 444,680, filed of even date herewith, in being a'quadruple expansion engine which does not employ the steam chamber used in the triple expansion engine, into which steam from high pressure cylinders exhausts before passing to the intermediate low pressure cylinders.

Having thus described the nature of my invention and the best means I know for carrying the same into practical effect, I claim- In quadruple expansion engines, the combination of a cylindrical main slide valve F having a port Q controlled by a central cylindrical expansion valve and communicating with port L of high pressure cylinder A, ports Q Q Q connected by annular passage R communicating with port L of cylinder A, port L of second cylinder A and port N of third cylinder A ports Q and Q connect, ed by annular passage R communicating with port N of third cylinder A and ports N and O of cylinder A, and a cylindrical valve chamber E having annular passage K communicating with port L of cylinder A,

passsage K communicating with port L of cylinder A passage K communicating with JAMES MARSHALL.

Witnesses:

HERBERT MARCH,

Leeds, Solicitor. CHAS. J N0. BRICE, Messenger at U. S. Consulate, Leeds. 

